Missing *-copy is an oversight, and will be corrected. It makes sense
to have the full range of copy operators, so code could still be
collection agnostic and yet clone a collection.
I don't see any advantage to having the full set of fold operators
though, except for the (weak) argument of a performance improvement in
dispatch when using the collection specific folder.
As for comparison, it seems that just adding some language defining
equal? over the collections would be sufficient. This would leave the
collections free to define equality for the values and the ordering they
contain. On the other hand, this would make a portable implementation
more difficult.
Scott
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